story of a fisherman feared lost at sea, after falling overboard. But remarkably, he survives after treading water for hours. Abc's john muller has the incredible story. Reporter: This is the incredible moment when a 51-year-old fisherman finally makes it back on land, after almost 24 harrowing hours stranded at sea. Steve moumouris' family, waiting in anticipation. He was in relatively good condition. Dehydrated. But obviously happy to be alive. Reporter: His story of survival begins wednesday afternoon, when moumouris set out for a fishing trip, off the coast of crystal river, florida. Around 1:00 p.M., He texted his wife this picture of a fish he caught. When he headed home, that's when a storm rolled? When moumouris hadn't made it home, his wife notified authorities. We had an intensive search. Including helicopters, c-130, small boats combing the area. And no sign of him. Reporter: Stranded at sea, moumouris said he could see the coast guard helicopters and found a shrimp boat. He got 100 yards from it. And they pulled up a and left. Reporter: Officials found his boat nine miles off the coast, but no sign of moumouris. He's battling the elements. Battling the sun. Hypother hypothermia. Reporter: On wednesday, another fisherman spotted moumouris about eight miles from the coast and rushed him to safety. I was driving. We looked and said, what is that? And then, we weren't sure. So, we headed that way. I don't know what else to say. It's a miracle. Reporter: For "good morning america," john muller, abc news, new york. Those moments, where he almost was saved. And not, to have it turn out the way it did, we're very thankful. Turn,

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